Synthesis of Carbon Nanotubes Using Layered Double Hydroxide with Various Metal Compositions as Catalyst Precursors

The synthesis of Ni-Al, Mg-Al, Mg-Fe, and Co-Al layered double hydroxides (LDHs) by a hydrothermal (HT) or homogeneous precipitation method using urea (UR), and the catalytic precursors of LDHs for the highly efficient synthesis of carbon nanotubes (CNTs) by water-assisted chemical vapor deposition (CVD) were investigated. CNTs could be efficiently synthesized by using LDH of different metal composites as the catalyst precursor, especially CNTs production was higher in the Co-Al LDH. The CNTs were synthesized by water-assisted CVD method using LDH as a catalyst precursor. The LDH platelet crystals were catalyzed by a reduction process, and then a carbon source was introduced so that CNTs grew from the LDH platelet crystals.